it's a massive tax that could cost the american economy more than half a trillion dollars a year. trillion with a t according to the national association of manufacturers. riley the former republican epa chief says something like that needs to be done. >> i think the epa has been led to a position where it's got to act. >> many disagree. among other things the epa cleanup operations of 40 years ago cost relatively little and most everyone benefits. in contrast an all out effort to lower the temperature of the planet assuming global warming is a real problem that humans can reverse would sheerl be the most complicated and expensive under taking in human history. >> the kinds of pollution in pittsburgh when i was growing up it's gone. i am grateful to that generation of the epa would help to make it happen. >> torpedo wood the epa latest mission reveals not a concern for the environment but a radical agenda that is less about the environment than most americans might image. as you will see later he discovered that in a college freshman dorm far from the corridors of power. >>> when